We learn about the FSA when we learn about the Compromise of 1850, of which it was a part. To pacify proslavery forces who were angry that California was allowed to enter the Union as a free state, the Compromise allowed slaveholding and trading to continue in Washington, DC, and upheld the “rights” of slaveholders to their “property”—enslaved people—throughout the Union.

This meant that if you lived in, say, Wisconsin, and had voted to pass personal liberty laws in your state outlawing slavery, those laws were overturned. Slavery would be upheld in “free” states, because slaveholders were allowed to enter free states and reclaim escaped people, and even pick up black citizens who had never been enslaved—the word of the slaveholder was accepted over the word of the black citizen and even the white citizens of the state. Whites were forced by the law to help slave-catchers, they were fined and jailed for failing to do so, or for helping an escapee, and whites were forced to live with the rescinding of the personal liberty laws they had voted for on a state level. Thus, slavery was basically enforced in every state of the Union, and outrage over this was expressed by many Northerners who had previously been publicly neutral about slavery.

If the Fugitive Slave Act was all about black slaves, asked Northerners, why was it fining, jailing, and threatening free whites? Why did it seem to focus just as much on attacking the liberties of northern white citizens as it did on preventing black Americans from gaining their liberty? It was just another example of the slave power perverting democracy and threatening free government.

When we hear people today, in 2017, talking about the laws and acts they are going to put in place to stop the alleged democracy-killing overflow of Spanish-speaking immigration to the United States, they sound a lot like people who would have liked the Fugitive Slave Act. Here is an NPR interview with Brandon Judd, president of the union that represents U.S. Border Patrol agents, the National Border Patrol Council, which endorsed Trump during the campaign, from yesterday:

INSKEEP: What do you think about the president’s effort to compel, if he can, local and state authorities to be more helpful to the Border Patrol and immigration authorities in doing their jobs and rounding up people who are here illegally?

JUDD: Well – so my understanding is that he’s not compelling them to help us round them up. But what he is saying is if they come in contact, if a police officer, say, from Phoenix Police Department – if a police officer from the Phoenix, Ariz., police department comes in contact with somebody that he knows is here or suspects that is here illegally, then his responsibility is to contact an immigration enforcement officer to come in and find out. It’s the same with me. As a Border Patrol agent, if I make a vehicle stop and I find that illegal activity is taking place outside of the laws that I enforce…

INSKEEP: Drunk driver for example.

JUDD: Exactly – it’s my responsibility to call the local law – the local law enforcement so that they can come out and take care of the problem.

INSKEEP: Are we not actually arguing about that much then? Because there are local authorities who are saying, yeah, yeah, if we find somebody who’s obviously in violation, we have to turn them over, but we do not want to make that our job. We don’t want it to be our job to seek them out or to hold people when otherwise there would not be reason to hold them.

JUDD: And it’s not going to be their job. It’s not going to be their job to go seek out illegal immigrants in the United States. That is immigrations officers’ jobs and it’s not theirs. But if they do come in contact with people that are in the country illegally, they should have a responsibility and duty to report people that are breaking the law.

Judd’s statements are disingenuous. How would that police office in Phoenix “know” that someone he meets is “here illegally” without a mechanism in place to track all immigrants and make their data available at all times to police, and require the police to consult it? There’s no way to “know” someone is a legal immigrant or not without looking up their information, which means asking/forcing the person you have “come in contact with” to give you their name, address, etc. And of course, “come in contact” with is blandly disingenuous as well: when do police officers “come in contact” with people? We’d wager that 95% of the time it’s by stopping them on the premise of a violation of the law. Judd himself puts contact in the context of a vehicle stop. So already we have a question of who is being stopped and why which has, of course, been asked for over a century in this country, beginning with black Americans stopped by police for no reason and extending to brown immigrants getting the same treatment.

The reporter’s characterization of police officers resisting being turned into immigrant-catchers is in line with all white Americans being forced into being slave-catchers in 1850. Judd says it won’t be the police officer’s job to “seek out illegal immigrants”, but reiterates that police officers who don’t turn in people who are here illegally are violating their duty and the law. If you get in trouble for failing to do something, you will find ways to do it. If police officers will be sanctioned for failing to turn in illegal immigrants, they will begin turning in illegal immigrants. They will look at the data, identify people here illegally in their cities and towns, stop them on another pretext, and turn them in.

And if the police must do this, eventually they will enlist the general public in helping them to do this. They will paint all immigrants here illegally as murderers, as Judd does later in the interview by saying “I think the country is going to be a lot safer. I really do, yes, absolutely. I mean, I was there with what they call the angel families, families that had children that were killed by persons that were in the United States illegally.” And once all illegal immigrants are child-murderers, it will be against the law not to seek them out and turn them in, for everyone.